Exception handling fixes

The following changes (against Poky, but apply cleanly with -p2 against bitbake master) are available in the git repository at:

git://git.yoctoproject.org/poky-contrib paule/bb-brokenexcept
http://git.yoctoproject.org/cgit.cgi/poky-contrib/log/?h=paule/bb-brokenexcept

Paul Eggleton (2):
fetch2: fix malformed URL causing a useless traceback
cooker: fix handling of exceptions during exception handling

 bitbake/lib/bb/cooker.py          |    9 +++++++--
 bitbake/lib/bb/fetch2/__init__.py |    4 ++--
 2 files changed, 9 insertions(+), 4 deletions(-)

1.7.9.5

The implementation of NoMethodError and MalformedUrl was broken - if you just set self.args in an exception class to a string it treats it as a list and then fails later on with a TypeError due to the number of arguments not matching up.

This nasty exception during exception handling was breaking the normal exception flow (fixed separately), which meant that if you had a malformed URL or invalid protocol in SRC_URI you would get the following:

ERROR: Command execution failed: Traceback (most recent call last):
File "/home/user/poky/poky/bitbake/lib/bb/command.py", line 84, in runAsyncCommand
self.cooker.updateCache()
File "/home/user/poky/poky/bitbake/lib/bb/cooker.py", line 1207, in updateCache
if not self.parser.parse_next():
File "/home/user/poky/poky/bitbake/lib/bb/cooker.py", line 1694, in parse_next
logger.error('Unable to parse %s', value.recipe,
AttributeError: 'exceptions.TypeError' object has no attribute 'recipe'

A specific fix for [YOCTO #2977].

---
 bitbake/lib/bb/fetch2/__init__.py |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

index fae1add..37f7d75 100644
@@ -54,7 +54,7 @@ class MalformedUrl(BBFetchException):
          msg = "The URL: '%s' is invalid and cannot be interpreted" % url
          self.url = url
          BBFetchException.__init__(self, msg)
-         self.args = url
+         self.args = (url,)
 
 class FetchError(BBFetchException):
     """General fetcher exception when something happens incorrectly"""

@@ -87,7 +87,7 @@ class NoMethodError(BBFetchException):
          msg = "Could not find a fetcher which supports the URL: '%s'" % url
          self.url = url
          BBFetchException.__init__(self, msg)
-         self.args = url
+         self.args = (url,)
 
 class MissingParameterError(BBFetchException):
     """Exception raised when a fetch method is missing a critical parameter in the url"""

1.7.9.5

If an exception occurs during handling another exception we were getting a useless traceback such as the following, after which BitBake froze:

ERROR: Command execution failed: Traceback (most recent call last):
File "/home/user/poky/poky/bitbake/lib/bb/command.py", line 84, in runAsyncCommand
self.cooker.updateCache()
File "/home/user/poky/poky/bitbake/lib/bb/cooker.py", line 1207, in updateCache
if not self.parser.parse_next():
File "/home/user/poky/poky/bitbake/lib/bb/cooker.py", line 1694, in parse_next
logger.error('Unable to parse %s', value.recipe,
AttributeError: 'exceptions.TypeError' object has no attribute 'recipe'

Fix this to print an actual traceback of the exception and exit gracefully (well, as gracefully as possible under the circumstances).

The general fix for [YOCTO #2977].

---
 bitbake/lib/bb/cooker.py |    9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

index 1b3bb84..19173ae 100644
@@ -1691,8 +1691,13 @@ class CookerParser(object):
         except Exception as exc:
             self.error += 1
             etype, value, tb = sys.exc_info()
-            logger.error('Unable to parse %s', value.recipe,
-                         exc_info=(etype, value, exc.traceback))
+            if hasattr(value, "recipe"):
+                logger.error('Unable to parse %s', value.recipe,
+                            exc_info=(etype, value, exc.traceback))
+            else:
+                # Most likely, an exception occurred during raising an exception
+                import traceback
+                logger.error('Exception during parse: %s' % traceback.format_exc())
             self.shutdown(clean=False)
             return False
 

1.7.9.5

Merged to master, thanks.

Richard